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Abstract Two-dimensional carbides and nitrides, known as MXenes, are promising for water-processable coatings due to their excellent electrical, thermal, and optical properties. However, depositing hydrophilic MXene nanosheets onto inert or hydrophobic polymer surfaces requires plasma treatment or chemical modification. This study demonstrates a universal salt-assisted assembly method that produces ultra-thin, uniform MXene coatings with exceptional mechanical stability and washability on various polymers, including high-performance polymers for extreme temperatures. The salt in the Ti₃C₂T_xcolloidal suspension reduces surface charges, enabling electrostatically hydrophobized MXene deposition on polymers. A library of salts was used to optimize assembly kinetics and coating morphology. A 170 nm MXene coating can reduce radiation temperature by ~200 °C on a 300 °C PEEK substrate, while the coating on Kevlar fabric provides comfort in extreme conditions, including outer space and polar regions. 

Abstract Intrinsically disordered protein regions (IDRs) are highly dynamic sequences that rapidly sample a collection of conformations over time. In the past several decades, IDRs have emerged as a major component of many proteomes, comprising ~30% of all eukaryotic protein sequences. Proteins with IDRs function in a wide range of biological pathways and are notably enriched in signaling cascades that respond to environmental stresses. Here, we identify and characterize intrinsic disorder in the soluble cytoplasmic N‐terminal domains of MSL8, MSL9, and MSL10, three members of the MscS‐like (MSL) family of mechanosensitive ion channels. In plants, MSL channels are proposed to mediate cell and organelle osmotic homeostasis. Bioinformatic tools unanimously predicted that the cytosolic N‐termini of MSL channels are intrinsically disordered. We examined the N‐terminus of MSL10 (MSL10 N ) as an exemplar of these IDRs and circular dichroism spectroscopy confirms its disorder. MSL10 N adopted a predominately helical structure when exposed to the helix‐inducing compound trifluoroethanol (TFE). Furthermore, in the presence of molecular crowding agents, MSL10 N underwent structural changes and exhibited alterations to its homotypic interaction favorability. Lastly, interrogations of collective behavior via in vitro imaging of condensates indicated that MSL8 N , MSL9 N , and MSL10 N have sharply differing propensities for self‐assembly into condensates, both inherently and in response to salt, temperature, and molecular crowding. Taken together, these data establish the N‐termini of MSL channels as intrinsically disordered regions with distinct biophysical properties and the potential to respond uniquely to changes in their physiochemical environment. 

Abstract Direct ink writing (DIW) using polymer‐particle composite inks is a new research area enabling a wide range of new functionalities. Despite extensive studies, there remains a need for a deeper understanding of how particle size and loading specifically influence printability, especially in the nano range. This work aims to systematically evaluate the effects of SiO₂nanoparticle size (26–847 nm) and loading on printability within a polydimethylsiloxane (PDMS) matrix. For the single‐layer printing process, which is influenced by the substrate properties, a 3D printing line analysis (3D‐PLA) is developed to monitor the top and side views of printed lines. It is found that line width varies with ink composition and substrate, while the line height decreases with solvent evaporation, indicating a strong confinement effect from the substrate. For multilayer structures, dual‐layer printing analysis (DLPA) is utilized to evaluate the printability. It is shown that DLPA is independent of the substrate and can be used to compare the printabilities from different inks. Both 3D‐PLA and DLPA can be correlated to the rheological behavior of the ink through ink rheology analysis (IRA). Finally, this research defined the design space for DIW by benchmarking the minimum and maximum particle loadings for printable composite inks.